1. Field of the Invention
This invention relates to central heating and cooling systems for residential home construction and more particularly to an improved low energy, high efficiency natural convection system of simplified construction.
2. Description of the Prior Art
Central heating and cooling systems as employed in most residential dwellings use forced air to transport heat or cool to the various rooms. In that regard, a single direction of flow is provided and the heated or cooled air must be delivered against the natural convection forces due to the change in the weight of the air as it is heated or cooled. Fans or blowers are required to force the air after being heated or cooled by passage over heat exchange coils to pass through relatively small ducts which adds to the loading. Such systems are known as high velocity injection systems, and for economy, the ducts are relatively small in size for the purpose of effecting maximum mixing of the air in the room where the air is being delivered. Actually, the air is delivered at a temperature which is quite different from the comfort level and mixing is needed to reduce the shock of highly contrasting air pockets and to catch the room corners and other places where the heat is being lost or gained to the extent that the conditioning is being locally distributed.
The high velocity is especially required when correction air is injected against gravity, as where the cool air is injected at the ceiling and the return is at the floor. If it were not for complete mixing, the cool air would go to the floor and return without much correction of the air in the room. In the reverse, the same is true of heating air which rises to the ceiling and creates a hot pocket if complete mixing is not accomplished. Such systems, partially due to the forced nature of the air, create objectionable drafts which are most noticeable in cold weather.
The present invention makes use of a simplified concept of natural convection which has been in use as far back as recorded history. For instance, the basic concept of natural convection is employed in coal furnaces which are placed in the basement of houses and heated air is sent to the rooms by convection through ducts, the air naturally rising to circulate through the various rooms on the given levels. Many dwellings in various times and places have been heated by convection outside the range of radiant heat from surfaces heated by direct contact with the fire, fireplace, pot belly stove, and the like.
The present invention adds to the natural convection to provide heating to the various rooms of a residential dwelling or the like, the same natural convection technique in the passage of air to be cooled over a cooling coil and employs the cooled air as its own means for distributing uniformly the cooling effect to the various rooms without objectionable drafts, etc.
The present invention employs low velocity, low temperature difference and maximum displacement of the air in a home with as little mixture as possible, does not reject a portion of the air within the building or replace the portion rejected and permits a layered movement of the air completely through the building structure being cooled and heated by convection to provide maximum efficiency and low energy heating and cooling to a residential dwelling or like building.